One sentence pattern in English consists of a subject, a linking verb, and a subject complement:
Because the subject complement names or describes the subject, it is sometimes mistaken for the subject. But the verb must agree with the subject, not the subject complement.
Tent and bag is the subject, not equipment.
Force is the subject, not women. If the corrected version seems awkward, make women the subject: Women are a major force in today’s economy—as earners, consumers, and investors.
Subject-verb agreement at a glance
When to use the -s (or -es) form of a present-tense verb
Exercises:
Subject-verb agreement 1
Subject-verb agreement 2
Subject-verb agreement 3
Subject-verb agreement 4
Related topic:
Subject complements